ORIGINAL: invertmast
I have done basic frame-ups of the smaller Yellow aircraft jet kits to where they are ready for paint and fit-out for as low as $250. For a china-arf like a skymaster,etc that the owner just wants a fit-out and initial setup, depending on the options (light system, smoke, etc etc etc) anywhere from $750+.
You work to cheap! At those prices you have to be working for around $.50/hr or less....
I have built several jets for people, mostly BVM stuff, sport jets somewhere around $6k finished, scale $8-10k based on the detail wanted. I don't do as much as I used to but I would not take one on unless the customer knows what he wants, what he can expect, and that it's finished on my schedule. I don't build to tight deadlines, but that's just me. There has to be communication between the builder and the customer.
DR